<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW --- - Unigine Tropics horrible performance with vblank_mode=2 (which is the default) or =3" href="https://bugs.freedesktop.org/show_bug.cgi?id=83012#c4">Comment # 4</a> on <a class="bz_bug_link bz_status_NEW " title="NEW --- - Unigine Tropics horrible performance with vblank_mode=2 (which is the default) or =3" href="https://bugs.freedesktop.org/show_bug.cgi?id=83012">bug 83012</a> from <a class="email" href="mailto:eero.t.tamminen@intel.com" title="Eero Tamminen <eero.t.tamminen@intel.com>"> Eero Tamminen</a> <pre>(In reply to <a href="show_bug.cgi?id=83012#c3">comment #3</a>) > Why don't we disable vsync by default? > I think that's what proprietary drivers do. Because that's relevant only for benchmarks. Normal applications want to present user complete (non-tearing) frames. Note: with DRI2, using fullscreen with vsync off causes X to do copy of every frame (which has clear performance penalty for memory bandwidth bound benchmarks). With DRI3, when Vsync is disabled on client side, the X side copy is done only every Vsync, but currently you would need quad buffering to avoid stalling from X server side synching, which isn't what Mesa does (see <a class="bz_bug_link bz_status_REOPENED " title="REOPENED --- - [DRI3 IVB/HSW/BYT-M/BDW Bisected] Warsow1.0/Xonotic 0.7/GpuTest_v0.5_triangle_fullscreen performance reduced by 20%~60%" href="show_bug.cgi?id=79715">bug 79715</a>). (If you're very close, but not quite at 60 or 30 FPS, this non-Vsync induced copy can cause your FPS even to slightly decrease compared to Vsync.)</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>